This invention relates to an apparatus for engaging the trailing edges of seriatim or sequentially discharged sheets of paper previously cut from a traveling web of paper to sequentially decelerate the cut sheets and lower the trailing edges thereof. By lowering a trailing edge, the leading edge of the next oncoming sheet freely travels over and overlaps the lowered trailing edge. The cut sheets are decelerated by sequentially pressing the trailing edges into engagement with the conveying run of a conveyor traveling at a relatively slower speed so that the sheets travel at essentially the same speed as the conveying run. The structure of this invention also contacts each sequential sheet such that at the moment of contact the sheet engaging member does not have any movement in the direction in which the sheet is traveling.
In the printing industry it is well known to utilize sheeters to receive a traveling web of printed paper as such web is discharged from the final printing rollers of the press. Such sheeters cut the traveling web into finished length printed products and then discharge the cut sheets successively or sequentially onto the first of a pair of elongated conveyors arranged in series. The first conveyor travels at a speed slightly faster than the speed at which the cut sheets are discharged from the cutting device such that the successive cut sheets are spaced from each other on the first conveyor in the direction of travel of the first conveyor. The second conveyor travels at a slower speed, with respect to the first conveyor, to receive the successive sheets in lengthwise overlapping relationship. Such overlapping relationship is commonly referred to as a shingled relationship. Such shingled sheets are sequentially discharged from the second conveyor to a sheet stacking platform in a well known manner and are removed as desired in a well known manner. In order to handle successive sheets with respect to the speed of the web traveling through the printing press the first and second conveyors are orbital conveyors having elongated conveying runs with the slower speed second conveyor traveling at about 10 to 15% of the web speed. Under such conditions the discharge of sheets onto the second conveyor creates various problems in shingling of the individual sheets. One problem in shingling such sheets is the necessity to either kickdown the trailing edge of each successive sheet or to kickdown and snub the forward travel of each successive sheet so that each sheet will travel at essentially the speed of the slower second conveyor.
U.S. Pat. No. 3,994,221 shows a rotary arm (or kickdown arm) with a wheel for engaging the trailing edge of each successive sheet; however, such rotary arm has a substantial velocity component in the direction of travel of the second conveyor such that the arm is not very effective at high press speeds to snub the travel of each sheet so that the sheets will travel with the second conveyor.